Vibration isolating support



May 20, 1952 c, HUSSMAN 2,597,244

VIBRATION ISOLATING SUPPORT Filed April 7, 1949 IN V EN TOR. Carl flus'snz am/ Patented May 20, 1952 UNIT OFF-ICE "2,597,244 7 x'n safims is omrniwe sucrose i Ali'iii'ciitimiMissile,-seri l86,073

i i 01. are s?) .52 Figure '1 is vafbot'tomplan view of a form of vibration isola'tingunit fthatislillustrative f the presentiinverition;

Fie y-21s a top. plan view of the unit shown in cupants of the office, as well as to'the 'occ'u'paritsfgy. Fig. '1;;

of space above'and below that in which 'suc'hfmachines are located. This is'particiilarly' truecf certain commonly used business machines which often weigh up to fifteen hundredortwofthous- Fig. 31is a-s'ecti'onal view taken on line 3-;3 of Fig.2; 7 p 7 'Fi'g. "4fis a sectional view of a second form of the "improved unit,'the section being takenon and pounds, since the vibrations generated by 10, linfe'il -l of Fig.5;

such machines frequently-aretransmitted-directly to the floor on which the machine's stand, and thence by the building structure "to'theo'flices'in adjacent parts of the building. Such heavy machines also notinfrequeritlyr damage the floors or floor coverings in instances wheretheyarapremitted to 'rest' directly thereon.

It is an object of the.present:inventioh-stoiprovide improved machine=supporting vibration-isolating units that pre'vent ormateriallyreducefthe;i2

transmission ofv annoying -'vibratioris;=to athelfloor on which the machines are supported'fiandifrom which they frequently are transmittedin -annoying volume to other portionsot thei -building.

shown in the accompanying drawings-;.-;are-designed for useunder"the-ilegs;-oi the-offending machines, such legs generallyxb'eing of metalaand in some instances being provided fwithe casters.

Figi5fis a top'plan view of the unit shownin Fig} '4 "and Fig; 'Gji's'a bottom plan view of said unit.

The unit'sho'wn in Figs. 1 to 3, inclusive, com- 15 pii'ses asui't'abl'e base -Ill for receivin thebottom 'end'fofaleg'of a machine 'to'be supported, and thevibrations'generatedby which are to be 'isolated jagainstftransmission in disturbing values to thesupportingflo'or. All'the legs of the ma- 0; chine will, fof'i'course; be, provided with similar units. fliifEigs. 2jand' 3 a conventional machine legis' indicated in'broken" lines and designated by nuineifalul. fIhefupperisurface 'of the base i0 is-f prcvided; with a perinrietrical flange or rim I2 The improved units hereinafter-described andag5 whihinefiect provides'are'c'essifor'retaining the The units-provide suitable: recesses for -receivingssoa examplefiandis"providedwith three columns or the various styles and shapes -of';-the lower.- ends of the legs commonly used, but the vibrationsisolating structures of the several units aregsimiiar and are designed to-accommodate-=ther-use pf defiectable or vibration damping; elements which operating characteristics might wen 'reqiiire'ffor I lobes lSthatareshoWn spaced 120 of are apart. Theldbes "are" integral "with solid "segmental portions i (6 of the base' member, the central "portion beneath the web or wall l4 being made hollow 5 forfred'ucing the amount ofmaterial required in casting the base. 1 Thebase, as shown; isprQvided withanieiiterior sidewall fl 1 that is :generally cylindrical in fappearance, and from which the lobes l-5-' -exten'd. Cylindrical cells or recesses l8 effective isolation of the objectionablevibrations 40. are provided "in thethree portions ofthe-base generated by them, isolating=units having vibration damping elements of different hamsteristics for giving maximiiineffic' 'zicy-under the respective-loads imposed-by the meichhis." likewise; a single machine may im'pose-fa weight on one leg than onI-theothers; and inisuch instances the improved units-employsd withisuch a machine, while in*appearanceidentieal, can be provided with vibratienngdamping --e1e'ments,

mm-[ed "by t he=lobe l5 and the-contiguous, porti ohs 1 $6.? These cells 'preferablyareformed by drilling from the 1ower surface of the base} the upperi-ends' of the'icells beingdefined by conical tee er- 45, -wa1is t9. Vibration isolating a: or :damping elementsare (adapted: for: insertion. in the lC911S,-i the elements'beingeindieatedvbyjnumeral 20,

, Ihe elementsw win the form show-n; are of. a

iami-natedistructurefcompr s p rposed layers that provide substantialf$ 1 1 -iSG1 -I Qlofgtabrio impregnated or coated with rubber or while supporting themachinein a-des-ired lev'el condition .r r 1,; v Other objects and advantagesof therim ovements will be apparemjr'rdm"ac nsiarano or other resilient material bonded together as by vulcanization, The .individual elements 20 me 'ci tlfrom alpreformed sheetiorlsl'ab of the amma'ted'material. "Eachelement 2 0'isprodrawingswherein'.

" in a cell is with the conical end incontacfiwith the conical wall 19, which provides a centering seat for the upper end of the element. The elements are shown as having cylindrical side walls, and are of a diameter less than the diameter of the cells, and hence provide annular spaces between the cell walls and the respective elements for purposes hereinafter mentioned. The lower portions of the elements are retained in axial alignment within the cells by means which afford adequate centering and stablizing action for the lower portions of the elements, such as rings 22 which may be of the same laminated compressible material as that of which the elements are formed.

The elements are of sufficient length to support the bases above and out of contact with a floor, the three-element units each providing three points of support for each leg of the machine. The elements of the character mentioned are longitudinally compressible under the loads imposed upon them by the supported machine. The extent of longitudinal compression or deflection of the elements under the supported loads should always be less than the elastic limits of the material, but short of that limit, the greater the compression, the greater is the vibration isolating value of the elements. Where the elements are made of a material such as the laminated material above mentioned, having uniform compression characteristics, elements of selected diameter can be employed in a given installation that affords a satisfactory degree of compression under the load. imposed by the particular supported machine. Where the weight of the machine is equally distributed on all supporting legs, the elements of each unit should be equal in compressive resistance, but in instances where one leg of the machine carries a greater portion of the total weight of the machine than the other legs, the isolating unit bearing the greater weight can be provided with elements of sufl'iciently greater diameter than the elements of the other units for giving equivalent vibration isolating effects and for maintaining the machine at a proper operating level.

It Will be seen that similar bases may be used with satisfactory results on different machines that vary quite materially in weight by providing elements 20 of appropriate cross-sectional area, formed of the same material or of different compressible resilient material, which, under the con ditions of use provide satisfactory vibration isolating results.

The cells of a unit are of greater diameter than the normal diameter of the elements to be used in the cells, and also are of greater diameter than the diameter of the elements when the latter have been longitudinally foreshortened and radially expanded by the weight of the supported machines, whereby actual contact of the walls of the cells with the cylindrical side walls of the elements is avoided, since such contact would result ina shortened path for transmission of vibrations from the base to the floor. The rings 22 being under some radial compression by the pressed fit within the annular spaces surrounding the elements, and being further compressed when the elements are radially expanded by the loads, perform a vibration isolating function between the cell walls and the respective elements, in addition to cooperating with the conical formations of the upper ends of the elements and the respective conical seats [9 in centering the elements within the cells.

The unit shown in Figs. 4 to 6, inclusive, comprises a base 23 which is rectangular in plan view and is provided with a rectangular-shaped recess 24 for receiving a leg of a machine, which may rest upon a bottom 25 that is closer to the floor than is the wall 13 of the above-described units. Opposed upper edges 26 of two of the walls defining the recess 24 are shown as beveled inwardly to provide supporting surfaces upon which a caster 21 of a machine leg may rest, where the caster is of a diameter that precludes its seating upon the floor or bottom wall 25.

The base 23 is provided, in the form illustrated, with three vertical bosses or lobes 28 which are vertically drilled from the lower side of the base to provide cells 29 having upper conical seats 20 for receiving vibration damping elements 3| ,which are similar to the elements 20 of the unit described above. Centering and retaining members 32 of annular form similar to the elements 22 are provided, as shown in Figs. 4 and 6. Since the vibration isolating characteristics of the structure shown in Figs. 4 to 6 are similar to those of the above described unit, further description of the modification is believed unnecessary.

While I have shown and described vibration isolating units that are illustrative of my improvements, are neat in appearance, simple in design and economical to manufacture, it will be apparent that various changes may be made in the units within the spirit of the invention defined by the appended claims.

I claim:

1. A vibration isolating support for use under a leg of a vibration generating machine comprising a base upon which the leg is adapted to rest, said base being provided with vertically arranged cells open at the lower side of the base and provided with upper conical walls, a resilient compressible vibration damping element in each cell provided with a conical upper end seating against the conical wall of the respective cell and extending beyond the lower ends of the cells a distance greater than the foreshortening of the element caused by the imposed load for supporting said base above the floor, said elements being of less diameter than said cells and being spaced from the vertical walls of the latter, and ring-shaped members disposed between the elements and the lower portions of the respective cell walls for retaining the elements out of contact with the walls of the cells.

2. A vibration isolating support for use under a leg of a vibration generating machine comprising a base upon which the leg is adapted to rest, said base being provided with a plurality of vertical cells of cylindrical form provided with conical walls at the upper ends and being open at the bottom of the base, a generally cylindricallyshaped vibration damping element in each cell of less diameter than the cell and provided with a conical upper end seating against said conical wall of the cell for centering the upper end of the element with respect to the cell, an annular member of vibration damping material surrounding each element and contacting the adjacent side wall of the cell adjacent the lower end of the latter for centering the lower portion of the element within the cell and resisting displacement of the element from said centered position, said elements being of material compressible under the imposed loads-and extending from the cells a distance greater than the extent of foreshortening thereof caused by the imposed load for sup- Number porting the base above a floor. 1,870,310 CARL HUSSMAN. 2,118,068 2,379,763

REFERENCES CITED 5 The following references are of record in the file of this patent: ggz

UNITED STATES PATENTS Number Name Date French Aug. 9, 1932 Buckley May 24, 1938 Sweet et a1 July 3, 1945 FOREIGN PATENTS Country Date France 1- May 1, 1936 

